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Re: sftp regarding a file transfer speed upgrade

From: Daniel Stenberg <>
Date: Wed, 18 Feb 2009 09:09:06 +0100 (CET)

On Wed, 18 Feb 2009, 오수경 wrote:

> The file upload and down road hour transport speed are slow too with sftp.

Yes, this is a known performance problem with libssh2.

> But the transmission at the time of 13M criterion file transfer time 1
> minutes become 30 second degree disturbance with sftp. This compares and
> different SFTP Client (FileZilla, winSCP etc.) time of 6~7 second degree and
> is slow too.

A known funtional work-around is to simply use multiple connections to upload
multiple files simultanouesly with libcurl, as then the libcurl+libssh2 combo
not only becomes comparable speed-wise but in fact it will actually outperform
several competing alternatives. Of course that won't help if you're only
down/uploading a single large file.

The effort to improve SCP and SFTP transfer speeds must be put into the
libssh2 code base.

Received on 2009-02-18